arabesque vs ornamentation

arabesque and ornamentation both are nouns.

Word	Noun	Adjective	Verb	Adverb
arabesque	Yes	No	No	No
ornamentation	Yes	No	No	No

As nouns, ornamentation is a hypernym of arabesque; that is, ornamentation is a word with a broader meaning than arabesque:

arabesque: an ornament that interlaces simulated foliage in an intricate design
ornamentation: something used to beautify

Other hypernyms of arabesque include decoration, ornament.

arabesque (noun)	ornamentation (noun)
an ornament that interlaces simulated foliage in an intricate design	the act of adding extraneous decorations to something
position in which the dancer has one leg raised behind and arms outstretched in a conventional pose	something used to beautify
	the state of being ornamented